In the present study, we demonstrated an increase in soma size in mPFC in ethanol-treated subjects relative to non-treated controls. There was no effect on soma size in NAC neurons. Because the difference in soma size is only relative to the non-treated group and not the intubated-control group, it is likely that the increase in soma size is the result of a synergy between the ethanol exposure and the stress of the administration procedures. A previous study identified a reduction in soma size of magnocellular, but not parvocellular, neurons in the lateral geniculate nucleus following moderate exposure to ethanol during the third trimester in monkeys (Papia et al., 2010). One possible mechanism underlying changes in soma size is a change in gene expression levels since Ransdell et al. (2010) recently demonstrated significant positive correlations between 18s rRNA expression in single isolated neurons and soma size. However, the functional significance of changes in soma size after ethanol exposure during development will need more empirical investigation.
